An identifier for a RailsTimeZone object (e.g., “Eastern Time (US & Canada)”, -5.hours).

A TZInfo::Timezone object.

An identifier for a TZInfo::Timezone object (e.g., “America/New_York”).

Here’s an example of how you might set Time.zone on a per request basis and
reset it when the request is done. current_user.time_zone just
needs to return a string identifying the user’s preferred time zone: